‘Yes, ma’am,’ Gillard said.

There was a collective sigh of relief as the chief constable walked out. Eye-rolling stares were exchanged, early morning yawns that had been kept stifled groaned out, eyes rubbed, coffee – even the vile police issue substance – urgently sought. Rob Townsend sprawled on his chair, his arms and legs splayed out. He looked utterly rogered. Gillard knew that the young research intelligence officer was still more than a little distracted by his relationship with the much-fancied crime scene investigator Kirsty Mockett. His self-confidence had grown, even as the quality of his work had deteriorated. What he was now about to be told would hopefully wake him up.

‘I’ve been having a think about this phone of Beatrice Ulbricht’s that travelled up to Brentford without her.’

‘That’s right,’ Townsend said, stifling a yawn. ‘Doesn’t make sense. Someone was on the train with her phone after she left at Earlsfield.’

‘No, Rob. I don’t think there was anybody using her phone by the time the train approached Clapham Junction.’

‘What about the text sent then? The cell site analysis showed it was sent in the vicinity of Clapham Junction, at about the time the train was pulling in.’

‘You’re forgetting one thing, Rob,’ Gillard said. ‘Something that you as our chief geek should know. When I looked at my own phone today, I found there was a setting to pre-set a text to go at a particular time. The message that was being responded to was received before Beatrice even got on the train. So the text could have been prepared, by her or someone else, before our mystery woman boarded the train.’

Townsend pursed his lips. ‘I suppose that’s possible, but why?’

‘False trail, Rob. As Rigby said, someone wants us to think that Beatrice got as far as London, and if she is missing, that is where they want us to look. Both the carefully placed phone, and our mystery woman’s journey are designed to build that piece of fiction. That would only make sense if Beatrice actually disappeared before she got on the train. And if that’s true, she’s in the middle of our patch. In Surrey.’

Townsend stroked his chin thoughtfully. ‘Deductive reasoning, yes.’ He yawned, and then realised something. ‘Forgot to mention that forensics finished with Beatrice’s phone late last night, so we can now have a look on the SIM card.’ He rubbed his hands together in anticipation. ‘We might be able to prove your point about the delayed texts.’

‘Did forensics find any dabs?’

‘The phone was smeared in Coke and coffee, probably from being in the bin, so not much survived. Still, they managed to lift a few. There’s nothing that obviously matches any criminal records, except for the lady at the waste transfer station, she’s got a bit of form from twenty years ago. Anyway, all the partials are now being looked at in Lewes to see if we’ve got anything else, which could take a few days, but they tell me not to raise our hopes.’